A man shot dead a nurse at a clinic outside Mthatha on Friday before shooting himself dead, the Eastern Cape health department said.
"A gun-wielding man entered Mhlakulo Community Health Centre and shot and killed the nurse in cold blood before turning the gun onto himself," said provincial health spokesperson Sizwe Kupelo.
The shooter was believed to be the nurse's husband.
Kupelo said the killing happened in full view of some patients. Both the nurse and the man died instantly.
"The motive of the killing is unknown, but it is believed to be a domestic dispute," he said.
"We want to reassure members of the public that this is just an isolated incident that seems to be domestic in nature," Kupelo said.
He said provincial health managers were visiting the clinic and police were investigating.
Kupelo added that provincial hospitals were in the process of installing CCTV cameras for the safety of staff and patients.